You can keep the Medieval look now even while managing another game
My mod manager used to wear whichever game you had open, which meant the Medieval chrome only existed while you were actually looking at Medieval. Now you pick the look in settings and it stays, so you can go sort out a Sims 4 folder in parchment and brass if you feel like it.
It is two materials rather than one. By daylight it is the ambition book and the build catalogue: parchment, a thin brass line, brown ink. After dark it is the live HUD, the same chrome carved out of dark wood with cream lettering. Both are in the game a screen apart, so neither one is a compromise.
The Medieval support itself has not changed. It finds the install even when the disc folder name is in another language, it scaffolds the Resource.cfg pointing at Mods/Packages, and it tells you when the d3dx9 proxy is missing so you are not sitting there wondering why a script mod is doing nothing. CC works without the proxy, script and core mods do not, and nothing in the app makes that obvious except saying so.
Free, no account, Windows Mac and Linux. Link in the comments.